Accumulated Other Comprehensive Income (Details Of The Reclassification From AOCI) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 4	$ (13)
Net income (loss)	(86)	(93)
Amounts reclassified from AOCI [Member]
Net income (loss)	(19)	(19)
Unrealized gains (losses) on AFS, net [Member] | Amounts reclassified from AOCI [Member]
Net realized investment gains (losses)	0	(5)
Instrument-specific credit risk of liabilities measured at fair value, net [Member] | Amounts reclassified from AOCI [Member]
Other net realized gains (losses)	0	(14)
Net gains (losses) on financial instruments at fair value and foreign exchange	$ (19)	$ 0